NI-14 EVALUATION OF PREOPERATIVE APPARENT DIFFUSION COEFFICIENT (ADC) OF PERITUMORAL LESION FOR PREDICTING SITE PRONE TO RECURRENCE IN PATIENTS WITH GLIOBLASTOMA

PURPOSE: In the surgery of glioblastoma (GBM), the maximum safe resection is desired in order to prevent recurrence. The purpose of this study is to make it possible to evaluate the site in which the recurrence after resection of the tumor occur, according to the findings in preoperative MRI, and to avoid the recurrence. METHOD: The 26 initial cases with GBM treated in our department was investigated. Preoperative MRI, postoperative MRI, and follow-up MRI during the course were analyzed in a retrospective view. In the FLAIR high-signal area around the contrast-enhanced tumor body in preoperative MRI, we investigated the relationship between the site and the ADC value, from the standpoint of whether a recurrence occurred or not. RESULTS: For preoperative MRI of 26 patients, the FLAIR high-signal region was set to a total of 54 ROI, and several values, such as the ADC values, were measured. In the preoperative images, ADC were higher in the site where the no recurrence occurred during the postoperative course and lower in the site where the recurrence occurred. CONCLUSION: In the FLAIR high-signal area around the tumor in preoperative images, ADC value is useful in evaluating whether it has tendency to develop the recurrence in the future course or not. It was suggested that significant recurrence occurs at part with low-ADC value. It is considered useful for the planning of the extent of resection in the surgery and the irradiation range in radiation treatment.